WaterQ

City Water Quality Rankings in California

599 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#385
Rowland Heights
County, CA
92 A
#386
Santa Cruz
County, CA
92 A
#387
Sunnyvale
County, CA
92 A
#388
Arbuckle
County, CA
91 A
#389
Camp Pendleton
County, CA
91 A
#390
Cloverdale
County, CA
91 A
#391
Fillmore
County, CA
91 A
#392
Forestville
County, CA
91 A
#393
Orland
County, CA
91 A
#394
Sacramento
County, CA
91 A
#395
Selma
County, CA
91 A
#396
Simi Valley
County, CA
91 A
#397
Sonora
County, CA
91 A
#398
Twentynine Palms
County, CA
91 A
#399
Angelus Oaks
County, CA
90 A
#400
Beale Afb
County, CA
90 A
#401
Big Pine
County, CA
90 A
#402
Brawley
County, CA
90 A
#403
Brentwood
County, CA
90 A
#404
Bridgeport
County, CA
90 A
#405
Cambria
County, CA
90 A
#406
Carnelian Bay
County, CA
90 A
#407
Clearlake Oak
County, CA
90 A
#408
Daly City
County, CA
90 A

Frequently Asked Questions

How are city water quality rankings calculated in California?

WaterQ city rankings are based on EPA SDWIS data across local public water systems, including contaminant detections, compliance violations, and recency-weighted score signals.

Can I compare two cities in California?

Yes. Use the city comparison links on this page or open the Compare tool to evaluate two cities side by side on score, grade, and water system coverage.

How often does WaterQ refresh city data?

City-level metrics refresh when new EPA data is processed. Check city pages for latest score and violation context.

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